Over the past year, Bitcoin's price has gone up more than 900 percent. It's a level of growth unheard of in traditional investing markets. Now, banks, governments, and everyday people are wondering if Bitcoin is the future of money, a giant bubble ready to pop or something in between.

As the showdown over the leadership of the Consumer Financial Protection Bureau continues, NPR's Robert Siegel talks with Georgetown University law professor Adam Levitin about what the law says about the succession of bureau directors.

The White House appointed Republican congressman Mick Mulvaney as interim director for the Consumer Financial Protection Bureau at the same time that Richard Cordray, its outgoing leader, said Leandra English would serve in the interim. So, who's in charge?